const c = Math.PI, x = 2 * c, u = 1e-6, m = x - u;

function E(e) {
    this._ += e[0];
    for (let t = 1, h = e.length; t < h; ++t)
        this._ += arguments[t] + e[t];
}

function A(e) {
    let t = Math.floor(e);
    if (!(t >= 0))
        throw new Error(`invalid digits: ${e}`);
    if (t > 15)
        return E;
    const h = 10 ** t;
    return function (i) {
        this._ += i[0];
        for (let s = 1, n = i.length; s < n; ++s)
            this._ += Math.round(arguments[s] * h) / h + i[s];
    };
}

class L {
    constructor(t) {
        this._x0 = this._y0 = // start of current subpath
            this._x1 = this._y1 = null, this._ = "", this._append = t == null ? E : A(t);
    }

    moveTo(t, h) {
        this._append`M${this._x0 = this._x1 = +t},${this._y0 = this._y1 = +h}`;
    }

    closePath() {
        this._x1 !== null && (this._x1 = this._x0, this._y1 = this._y0, this._append`Z`);
    }

    lineTo(t, h) {
        this._append`L${this._x1 = +t},${this._y1 = +h}`;
    }

    quadraticCurveTo(t, h, i, s) {
        this._append`Q${+t},${+h},${this._x1 = +i},${this._y1 = +s}`;
    }

    bezierCurveTo(t, h, i, s, n, $) {
        this._append`C${+t},${+h},${+i},${+s},${this._x1 = +n},${this._y1 = +$}`;
    }

    arcTo(t, h, i, s, n) {
        if (t = +t, h = +h, i = +i, s = +s, n = +n, n < 0)
            throw new Error(`negative radius: ${n}`);
        let $ = this._x1, r = this._y1, p = i - t, l = s - h, _ = $ - t, o = r - h, a = _ * _ + o * o;
        if (this._x1 === null)
            this._append`M${this._x1 = t},${this._y1 = h}`;
        else if (a > u)
            if (!(Math.abs(o * p - l * _) > u) || !n)
                this._append`L${this._x1 = t},${this._y1 = h}`;
            else {
                let d = i - $, f = s - r, y = p * p + l * l, T = d * d + f * f, g = Math.sqrt(y), v = Math.sqrt(a),
                    w = n * Math.tan((c - Math.acos((y + a - T) / (2 * g * v))) / 2), M = w / v, b = w / g;
                Math.abs(M - 1) > u && this._append`L${t + M * _},${h + M * o}`, this._append`A${n},${n},0,0,${+(o * d > _ * f)},${this._x1 = t + b * p},${this._y1 = h + b * l}`;
            }
    }

    arc(t, h, i, s, n, $) {
        if (t = +t, h = +h, i = +i, $ = !!$, i < 0)
            throw new Error(`negative radius: ${i}`);
        let r = i * Math.cos(s), p = i * Math.sin(s), l = t + r, _ = h + p, o = 1 ^ $, a = $ ? s - n : n - s;
        this._x1 === null ? this._append`M${l},${_}` : (Math.abs(this._x1 - l) > u || Math.abs(this._y1 - _) > u) && this._append`L${l},${_}`, i && (a < 0 && (a = a % x + x), a > m ? this._append`A${i},${i},0,1,${o},${t - r},${h - p}A${i},${i},0,1,${o},${this._x1 = l},${this._y1 = _}` : a > u && this._append`A${i},${i},0,${+(a >= c)},${o},${this._x1 = t + i * Math.cos(n)},${this._y1 = h + i * Math.sin(n)}`);
    }

    rect(t, h, i, s) {
        this._append`M${this._x0 = this._x1 = +t},${this._y0 = this._y1 = +h}h${i = +i}v${+s}h${-i}Z`;
    }

    toString() {
        return this._;
    }
}

function P(e) {
    return function () {
        return e;
    };
}

function q(e) {
    let t = 3;
    return e.digits = function (h) {
        if (!arguments.length)
            return t;
        if (h == null)
            t = null;
        else {
            const i = Math.floor(h);
            if (!(i >= 0))
                throw new RangeError(`invalid digits: ${h}`);
            t = i;
        }
        return e;
    }, () => new L(t);
}

export {
    P as c,
    q as w
};
